The amount of missing tax collected by HM Revenue and Customs officers investigating fraud and evasion is up by nearly 50% in the past two years.

Efficiency savings means HMRC now collects 15 times more tax than it costs to run. It's been done by focusing on VAT fraud and high risk cases.

We're taking about criminal evasion here which, according to HMRC, costs £15bn a year. Not the legal - but morally questionable - tax avoidance by loophole which brings the missing tax to £42bn a year.

(Independent expert Richard Murphy reckons those figures are too low and estimates that evasion costs £25bn a year and avoidance £70bn. He adds unpaid or uncollected tax worth £26bn and comes up with a total "tax gap" of £120bn. If Richard's right and we could collect it all - OK, it's a big if - then bye-bye austerity Britain.)

But can HMRC continue the excellent work? The coalition wants more, another £7bn a year in tax revenue at the same time as cutting the HMRC budget by 15%. It's begun closing some of the loopholes.